PROCELLARIID/E — THE PETRELS — PUFFINUS. 379 



The egg is large, and somewhat rounded in shape, pure white in color, and without 

 spots, or sometimes white, washed with gray ; it measures 2.75 inches in its greater 

 diameter, and 1.85 in its smaller. The female alone performs the duties of incuba- 

 tion ; and as soon as the young bird is hatched, abandons her nest and hides the 

 nestling in some other retreat in the neighborhood, and visits it only during the 

 night to bring its food. 



This bird feeds principally on fish, mollusks, and crustaceans, which it collects 

 from the surface of the water. It is most commonly seen on the approach of a 

 tempest, or during the morning or evening twilight. The young, when they first 

 appear, are covered with a thick downy coat of a bright ashy gray. 



Puffinus borealis. 



THE NORTHERN SHEARWATER. 



Puffinus borealis, Cory, Bull. Nutt. Orn. Club, VI. no. 2, April, 1881, 84 (coast of Massachusetts).— 

 Job, ib. VIII. Oct. 1883, 244 (off Cape Cod, in August). 



Sp. Char. ''Above, brownish ash, the feathers of the back becoming pale at the tips, those 

 on the nape ami sides of the neck narrowly tipped with white ; on the skies of the neck and head 

 the ash and white gradually mingling, as in P. Kiihlii. Tips of the upper tail-coverts white. Under 

 eyelid white, showing clearly in contrast with the ashy gray of the head. The first three prima- 

 ries arc light ash on the inner webs. Winga and tail brownish gray. Under parts white, slightly 

 touched with ash on the flanks ; lining of wings white. Under tail-coverts white, the longest 

 tinged with ash near the ends, which extend nearly to the tips of the longest tail-feathers. Out- 

 side of foot greenish black, inside and webs dull orange ; bill pale yellowish at the base, shading 

 into greenish black, but again becoming pale near the tip. 



" Length, 20.50 inches ; wing, 14.50 ; bill (straight line to tip), 2.25, depth at base, .75 ; tail, 

 6.50 ; tarsus, 2.20. 



" The type specimen of this Shearwater was killed near Chatham Island, Cape Cod, Mass., 

 on the 11th of October last. Being unacquainted with it, I showed it to some fishermen, and 

 requested them to procure any birds they might meet with resembling it. During the afternoon 

 one of the boats returned bringing a number of birds of this species. The men stated that they 

 had met with a flock a short distance from shore, and had shot several and knocked others down 

 with their oars. According to their statement, after firing the first shot the birds flew about them 

 in a dazed manner, often passing within a few feet of the boat" (Cory, I. c). 



This Shearwater, of which the National Museum has received two specimens since the above 

 was written, is a near ally of P. Kuhlii, but is decidedly larger, and somewhat different in color- 

 ation. The coloration of the bill and other soft parts are in particular supposed to differ much in 

 life and in freshly killed examples of the two species. The two examples in the National Collection 

 measure as follows : — 



No. 82488, male adult, Chatham, Mass., Oct. 11, 1880. Wing, 13.75 inches ; tail, 5.60 ; culmen, 

 2.10 ; depth of bill through base, .80 ; tarsus, 2.25 ; middle toe, 2.45. 



No. 93040, adult (sex not given), same locality, Oct. 12, 1880. Wing, 14.00 inches ; tail, 5.70 ; 

 culmen, 2.25 ; depth of bill through base, .80 ; tarsus, 2.15 ; middle toe, 2.30. 



The habits and distribution of this recently discovered species are little known, the following, 

 by Mr. Herbert K. Job, in the " Nuttall Bulletin " (VIII. 244), comprising nearly all there is on 

 record : — 



" On the 2d of last August I was out in a yacht collecting sea-birds, about thirty miles east- 

 ward from the southeast end of Cape Cod. Wilson's Petrels, Pomarine Skuas, and Greater and 

 Sooty Shearwaters were abundant. Both these Shearwaters were often seen sitting on the water 

 in flocks, associating freely with one another, and were easily approached. 



"On one occasion 1 sailed up to quite a large flock, and shot a P. fuliginosus. As the rest rose, 

 I suddenly perceived amongst them a Shearwater entirely new to me ; and my other barrel soon 



